Electrical and Computer Engineering

Rebecca Baturin

Chris Boyle

Charles Urbanowski

Daniel Willmott

November 20th, 2014

MDR PresentationStarTrack

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Team Introductions

Rebecca Baturin, EE

Daniel Willmott, EECharles Urbanowski, EE

Chris Boyle, CSE

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What is StarTrack?

What is our motivation?

We want to provide a low cost, accurate, and intuitive tool for taking photos of the night sky

Who is it for?

StarTrack is geared toward hobbyists who already own a DSLR camera

What does it do?

StarTrack automates the process of finding interesting targets in the sky

Allows for wireless control of both the mount movements and the camera shutter

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Concerns from PDR: Accuracy

Test photos taken with manual tracking mount• 90 second exposures

• Mount radius of ~7.14 inches meant that screw could be turned by hand at 1RPM (used a watch for reference)

• Average star size is 25 by 30 pixels

Goal is to produce images with stars that are circular as opposed to oblong

The more accurate StarTrack becomes, the less distortion we will see in our final image

During a 5 minute exposure, the apparent motion of the stars is 1.25°• For 99% accuracy we will need to have tracking capabilities

within 0.75 arc minutes (0.0125°)

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Concerns from PDR: Wi-Fi vs. Bluetooth

Wireless Networking in Rural Areas:

Unreliable

Added cost of interfacing with mobile networks

Bluetooth Low Energy:

Has comparable range to Wireless

Lower power consumption over time

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Block Diagram

Subsystem Owners:• Red- Charles

• Blue- Chris

• Green- Daniel

• Purple- Rebecca

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General Requirements (Updated)

Wireless Control The mount and camera must be wirelessly controlled through a mobile application

from up to 100 meters away

Mount Control The mount must be programmable to take a succession of at least 5 exposures of 5

minutes each at each target

The mount must continuously operate for at least 8 hours and must also be rechargeable

The mount must support a camera and lens of up to 2 pounds

Motor Automation Once placed facing North, the North Star motor must be able to align the mount with

the North Star. During operation, the mount must not deviate from alignment by more than 0.75 arc minutes

Using inputs from the Star Database, the Pan/Tilt motors must be able to position the camera so that the specified object is in its FOV

The Tracker motor must provide accurate tracking. For each 5 minute exposure, the mount must be within 0.75 arc minutes of its ideal position

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MDR Deliverables

Rebecca Baturin:

Determine accurate tracking algorithm and program microcontroller

Build camera interface and demonstrate control of camera settings

Chris Boyle:

Build iOS application that can send coordinates and camera settings over Bluetooth

Program Pan/Tilt mount to point at a specific coordinate in the sky

Charles Urbanowski:

Build power supply to appropriately operate all components of StarTrack

Build a compiled database of 15 noteworthy constellations

Daniel Willmott:

Send and receive data from the microcontroller via Bluetooth

Receive GPS data on the microcontroller

Be able to move North Star motor via microcontroller

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Star Database (Charlie)

Deliverable :

Build a compiled database of 15 noteworthy constellations

Accomplished:

Modular database of 15 constellations has been built to allow for rapid access and future additions

Each object includes their name (and possible nickname) and their ICRS coordinates, including right ascension points and declination coordinates

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Mobile Application (Chris)

Deliverable :

Build iOS application that can send coordinates and camera settings over Bluetooth

Accomplished:

Built iOS app that can connect to a Bluetooth peripheral and send the parameters and a message to start tracking

Built OS X app to act as the peripheral for testing and demonstration

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Wireless Communication System (Dan)

Deliverable :

Send and receive data from the microcontroller via Bluetooth

Accomplished:

Able to enter configuration mode on Bluetooth module via an Android phone

Able to send data to the microcontroller to turn on and off an LED

Able to receive data from the microcontroller confirming the action

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North Star Motor and Control System (Dan)

Deliverable :

Receive GPS data on the microcontroller

Be able to move North Star motor via microcontroller

Accomplished:

Able to receive and parse GPS data on microcontroller

Google Maps Confirmation Link

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North Star Motor and Control System (Dan)

Deliverable :

Receive GPS data on the microcontroller

Be able to move North Star motor via microcontroller

Accomplished:

Able to send real time serial data to a stepper motor and control the number of revolutions

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Tracker Motor and Control System (Rebecca)

Deliverable :

Determine accurate tracking algorithm and program microcontroller

Accomplished:

Able to change stepper motor speed for set time intervals

Tracking algorithm has been determined, and will be tested once the physical mount has been built

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Pan/Tilt Motor and Control System (Chris)

Deliverable :

Program Pan/Tilt mount to point at a specific coordinate in the sky

Accomplished:

Able to move pan/tilt mount to desired points in a spherical coordinate system

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DSLR Camera Interface and Control (Rebecca)

Deliverable:

Build camera interface and demonstrate control of camera settings

Accomplished:

Control of camera shutter is provided by the microcontroller at a user specified interval

All other camera settings are static and are initialized by the user while setting up the mount

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Rechargeable Power Supply (Charlie)

Deliverable:

Build power supply to appropriately operate all components of StarTrack

Accomplished:

Power supply is built and outputting near-ideal voltages

Portable components have been researched for future testing

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CDR Deliverables

Demonstration of Entire System

iOS app initializes StarTrack mount• iOS app sends command to microcontroller to align mount

• Microcontroller gathers GPS Data and uses North Star Motor to align StarTrack mount with the North Star

User specifies desired sky target via iOS app• Star coordinates are sent to the microcontroller via the iOS app

• Pan/Tilt mount moves camera to desired coordinates

User specifies desired operation parameters• iOS app sends command to microcontroller to begin tracking

• DSLR receives shutter commands from the microcontroller to take images at specified intervals (using pre-set exposure lengths)

Tracker returns to ready state, and continues with the script• Tracker motor returns StarTrack mount to a closed position

• iOS app notifies user that StarTrack is ready to image another target

Once script is completed, the North Star Motor returns to a closed position

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Gantt Chart

Build physical mount

• Integrate stepper motors with mount

• Integrate pan tilt with mount

• Fully functional wired mount

• Powered mount

• Wirelessly controlled mount

• Autonomous mount

Subsystem Owners:

• Red- Charles

• Blue- Chris

• Green- Daniel

• Purple- Rebecca

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Demos